On Mon, Jul 29, 2024 at 9:16 AM Jann Horn <jannh@xxxxxxxxxx> wrote:
>
> On Thu, Jul 25, 2024 at 12:52 AM Andrii Nakryiko <andrii@xxxxxxxxxx> wrote:
> > Harden build ID parsing logic some more, adding explicit READ_ONCE()
> > when fetching values that we then use to check correctness and various
> > note iteration invariants.
> >
> > Suggested-by: Andi Kleen <ak@xxxxxxxxxxxxxxx>
> > Signed-off-by: Andrii Nakryiko <andrii@xxxxxxxxxx>
>
> If I understand correctly, build ID parsing is already exposed to
> untrusted code since commit 88a16a130933 ("perf: Add build id data in
> mmap2 event"), which first landed in v5.12, right? Can you put fixes
> for parsing build IDs from untrusted memory at the start of your
> series with stable backport markers, so that we can fix this on
> existing systems? Or should this be fixed on existing stable trees
> with a separate stable-only fix?
Ok, I'll try to refactor to have fixes upfront before we do the
freader_fetch changes. If that turns out to be too convoluted, we can
think about separate stable-only fixes.
